How do I set up outdoor lighting?

Solar, low-voltage and mains — which is which, what you can install yourself, and how to avoid a garden that looks like a runway.

Difficulty: beginner
Time: 2 hr
Read: 2 min
Safety: warning

Short answer

Solar for simplicity, low-voltage plug-in kits for reliability, mains only via an electrician. Aim light at what you want to see rather than out at eye level — glare is what makes garden lighting unpleasant.

Outdoor lighting has a large effect on how much an outdoor space is used, and it goes wrong in two predictable ways: too bright, and pointed at people rather than at things.

Safety

Any mains electrical work outdoors is notifiable and must be done by a registered electrician — this includes fitting an outdoor socket or wiring mains lighting. Solar and battery lighting, and low-voltage systems plugged into an existing outdoor socket, are safe DIY. Never run an indoor extension lead outside, and never through a partly-open window or door.

Step by step

Decide what the lighting is for.Safety on a path, atmosphere for sitting, or security. They want completely different fittings and brightness, and combining them badly gives you a floodlit patio nobody wants to sit on.
Choose the system that matches your ambition.Solar: no wiring, modest output, dependent on sun. Low-voltage: a transformer plugged into an existing outdoor socket, reliable and DIY-safe. Mains: brightest and permanent, and requires an electrician.
Understand the legal line.Installing a new outdoor socket or wiring mains lighting is notifiable electrical work. Plugging a low-voltage transformer into an existing outdoor socket is not.
Light objects, not eyes.Uplight a tree, graze a wall, mark the edge of a step. Fittings at eye level that shine outwards create glare and make everything else look darker.
Use warm colour temperatures.Around 2700K. Cool white looks clinical outdoors and is markedly less flattering to planting and brickwork.
Use much less light than you expect.Eyes adjust to darkness. A garden needs a fraction of indoor light levels, and over-lighting is the most common mistake.
Check the IP rating.Fittings must be rated for outdoor use — at least IP44 for general exposure, higher for anything in or near water. Indoor fittings outdoors fail quickly and dangerously.
Consider your neighbours and wildlife.Light spilling into someone's bedroom causes genuine disputes, and permanent bright lighting disrupts nocturnal wildlife. Timers and motion sensors solve both.

Tips

Solar lights need genuine direct sun for most of the day. In a shaded garden they will disappoint regardless of what the packet claims.
String lights at low level around a seating area do more for atmosphere than any number of spotlights.
Put security lighting on a motion sensor rather than leaving it on. It is more effective, cheaper and much better for neighbours.

Common mistakes

Running an indoor extension lead outside — It is not rated for moisture and creates a real electrocution risk. Use outdoor-rated equipment and a proper outdoor socket.
Over-lighting — Eyes adapt to low light. A brightly lit garden creates glare and dark patches, and it is unpleasant to sit in.

Questions people ask

Can I install outdoor lighting myself?

Solar, battery and low-voltage systems plugged into an existing outdoor socket, yes. New outdoor sockets and mains-wired lighting are notifiable work needing a registered electrician.

Are solar garden lights any good?

In a genuinely sunny position, reasonable for atmosphere. In shade, or for anything you need to rely on, low-voltage wired lighting is much better.